Roadmap on energy harvesting materials

Abstract

Ambient energy harvesting has great potential to contribute to sustainable development and address growing environmental challenges. Converting waste energy from energy-intensive processes and systems (e.g., combustion engines and furnaces) is crucial to reducing their environmental impact and achieving net-zero emissions. Compact energy harvesters will also be key to powering the exponentially growing smart devices ecosystem that is part of the Internet of Things, thus enabling futuristic applications that can improve our quality of life (e.g., smart homes, smart cities, smart manufacturing, and smart healthcare). To achieve these goals, innovative materials are needed to efficiently convert ambient energy into electricity through various physical mechanisms, such as the photovoltaic effect, thermoelectricity, piezoelectricity, triboelectricity, and electromagnetic power transfer. By bringing together the perspectives of experts in various types of energy harvesting materials, this Roadmap provides extensive insights into recent advances and present challenges in the field. Additionally, the Roadmap analyzes the key performance metrics of these technologies in relation to their ultimate energy conversion limits. Building on these insights, the Roadmap outlines promising directions for future research to fully harness the potential of energy harvesting materials for green energy anytime, anywhere.

Air-Stable Lead-Free Antimony-Based Perovskite Inspired Solar Cells and Modules

“…We forecast that this superior basis provides the possibility for large-scale module fabrication, which is an important consideration for a technology with industrial potential. 13 Sb-based PIMs form in an A 3 Sb 2 X 9 (e.g., A = Cs + , MA + ; X = I − , Cl − ) crystal structure. 46 MA 3 Sb 2 I 9−x Cl x and Cs 3 Sb 2 I 9−x Cl x single-cation Sb-based perovskite-inspired solar cells (PISCs) are the most extensively studied.…”

“…For the above reasons, new Sb-based perovskite inspired materials (PIMs) have started to be developed and studied to potentially mitigate the problem of toxicity of Pb and of air instability of Sn-based materials. ,− Trivalent Sb-based perovskite PIMs have generally exhibited suitable chemical stability. ,− However, no solar modules have been reported for PIMs. We forecast that this superior basis provides the possibility for large-scale module fabrication, which is an important consideration for a technology with industrial potential …”

“…Over the past decade, lead-halide perovskite solar cells (PSCs) have made tremendous progress with power conversion efficiency (PCE) reaching 26.1%. , Although the matter is complex and must be analyzed from different angles (e.g., toxicity of elements and derivative compounds according to different tests, environmental footprint, life cycle analysis, which depends also on efficiency and performance etc. ), − and despite the excellent properties of Pb-based perovskites and low amounts found in PV cells and electronic products in which they will be integrated, the toxicity of heavy metal Pb may remain a concern for some of its practical applications. ,, Therefore, in recent years, scientists have initiated actions on developing potentially low-toxicity eco-friendly perovskite alternatives to produce the next-generation lead-free PSCs. − Major alternative classes to lead–halide perovskite comprise tin (Sn)-based − and germanium-based perovskites and derivatives, ,, double perovskites, , and bismuth (Bi)-based − and antimony (Sb)-based perovskite derivatives. − In this race to lead-free compounds, Sn-based perovskites have been more prominent with their PCE exceeding 14%. − Historically, these perovskites suffer from severe instability in the air; e.g., MASnI 3 undergoes chemical decomposition within seconds, due to the undesired oxidation of Sn 2+ into Sn 4+ . − Such poor stability together with unfortunate film morphology are the main reasons why fully laser-patterned (P1, P2, P3) working lead-free large-area PV modules had not been reported so far, since the large lasers used for module manufacturing are placed outside the glovebox and the laser scribing process often takes over tens of minutes or even hours …”

Origin of off-centering effect and the influence on heat transport in thermoelectrics

“…The energy conversion efficiency of a thermoelectric device is primarily determined by the ZT value of thermoelectric material, which is given as ZT = (S 2 σ)T/κ. It is obvious that good thermoelectric materials are generally required to have both high Seebeck coefficients (S), and high electrical conductivity (σ), along with low thermal conductivity (κ) [3][4][5][6]. However, the actual challenge is that these thermal and electronic transport properties are, in fact, strongly correlated with the carrier concentration and effective mass.…”

Editorial: Focus on green nanomaterials for a sustainable internet of things

“…Amidst this pursuit, nanomaterials have risen to a pivotal position [3], offering solutions that not only enhance performance but also align with our aspirations for a greener future. Indeed, nanomaterials are driving progress in a wide spectrum of applications: from sensors [4,5] energy harvesters [6,7], and energy conversion and storage devices [8], to light emitting devices [9,10], and quantum information science [11]. Their attributes offer a wide range of opportunities for tailoring their properties to suit specific requirements, making them highly attractive for IoT applications.…”